1. Field of the Invention
The invention generally relates to an optical device and a projection system, and more particularly, to an optical device with an optical sensor and a projection system.
2. Description of Related Art
FIG. 1 is a diagram of a conventional projection system 100. Referring to FIG. 1, the projection system 100 includes a projector 110, a personal computer (PC) 120 and a mouse 140. The projector 110 is connected to the PC 120 through a transmission line 122, and the mouse 140 is connected to the PC 120 through a signal line 124. The PC 120 transmits an image signal to the projector 110, so that the projector 110 projects a projection image 130. A user operates the mouse 140 to generate a corresponding position signal so as to control the moving of a cursor 150 in the projection image 130.
From the user's viewpoint, the relative position and arrangement of the projector 110, the PC 120, and the mouse 140 are limited by the lengths of the transmission cable 122 and the signal cable 124. Thus, inconvenience in using the projection system 100 may be caused if the transmission cable 122 and the signal cable 124 are too short. On the other hand, the user needs to sit or stand near the PC 120 to operate the mouse 140 so as to control the cursor 150 when the user gives a briefing. However, it's difficult for the user to closely interact with other participants.
On pages 51-61 of the specifications of Dell's projector model 4610X, the above-mentioned connection between the projector and the PC is realized in a wireless manner so that the projector receives the image signal from the PC and then projects the image according to the received image signal. However, when the user utilizes the projector of the above-mentioned model, the moving of the cursor in the image is controlled by an indication device (for example, mouse) connected to the PC.